A Feb. 17 article published in the New England Journal of Medicine, “Safety and Efficacy of the BNT162b2 [Pfizer-BioNTech] mRNA Covid-19 Vaccine” suggests that the efficacy of even a single dose of the Pfizer and Moderna mRNA vaccines could provide 92% efficacy, not much less than the 95% provided by the full two-dose regimen. The data do not indicate the longer-term effectiveness of receiving one dose versus two, and must therefore be taken with a grain of salt.
But the short-term data suggest that it may be better to provide more people with single doses of these two-dose vaccines than to provide fewer people with two doses.
